1. Field of the Invention
The present invention relates to nonwoven fabrics and particularly those nonwoven fabrics intended for limited use or disposable applications. Examples include medical fabrics for disposable drapes, gowns, table covers and the like intended for hospital, clinic, or other health care uses. Examples of other laboratory, industrial, or even consumer uses where clothlike attributes are desired will be apparent to those skilled in the art. With appropriate treatments nonwoven webs intended for such end uses may be imparted desirable properties such as water repellency, alcohol repellency, fire retardency, and the like. More particularly, the present invention is directed to such nonwoven webs made by combining multiple web components into an integrated laminate demonstrating the desired properties.
2. Description of the Prior Art
Nonwoven webs, including those of laminate constructions, are, of course, well-known. Early constructions involved treatment of paper to improve its wet strength properties. Later developments related to reinforcement of paper, including tissue, by means of scrims of machine direction and cross direction filaments and other fibrous webs. An example of such a scrim laminate with creped cellulose wadding is described in U.S. Pat. No. 3,837,996 to Braun and Knauer dated Sept. 24, 1974. That patent also describes treatments to achieve desired properties such as water repellency. Other laminates of tissue and nonwoven webs are described in U.S. Pat. No. 3,900,632 to Robinson dated Aug. 19, 1975, U.S. Pat. No. 3,870,592 to Brock and Hudson dated Mar. 11, 1975, and U.S. Pat. No. 3,679,515 to Capell and Wilson dated July 25, 1972, for example. Meltblown microfiber web laminates as nonwovens useful for medical applications are known and described, for example, in U.S. Pat. No. 4,041,203 to Brock and Meitner dated Aug. 9, 1977 and in U.S. Pat. No. 4,196,245 to Kitson, Gilbert and Israel dated Apr. 1, 1980. Various softening treatments for nonwoven tissue web laminates are described as improving softness and the like in U.S. Pat. No. 4,113,911 to LaFitte and Camden dated Sept. 12, 1978, for example. In spite of these and other attempts to produce at high speed and low cost a nonwoven fabric having clothlike attributes, particularly as to feel, noise, drape, and strength, there remains desired further improvement towards that objective. Existing materials tend to be paper-like, rattle, and lack required strength properties.